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Held For Sale (Details) $ in Millions, $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 USD ($) | Dec. 31, 2018 CAD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 CAD ($)
Long Lived Assets Held-for-sale [Line Items] |  |  |  |
Property, Plant and Equipment, Net |  | $ 18,712 |  | $ 16,995
New England Gas Generating Facilities [Member] | Emera Energy Services [Member] |  |  |  |
Long Lived Assets Held-for-sale [Line Items] |  |  |  |
Proceeds From Sale Of Property Plant And Equipment | $ 590 |  |  |
Property, Plant and Equipment, Net |  | $ 777 | $ 570 |

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